MILL. 
milk is small in quantity, insipid, and of a 
pale yellow. The butter of asses’ milk is 
always white, soft, and disposed to be ran- 
cid. That from goat’s milk is abundant, 
white, and soft. The butter from ewe’s 
milk is yellow and soft : that from mare’s 
milk has but little consistence, and is readily 
decomposed. 
3. The caseous part of milk varies in dif- 
ferent animals. That from the milk of the 
cow is bulky, and retains much serum. That 
from women’s milk is small in quantity, has 
an unctuous feel, and but a small portion of 
whey. The curd of asses’ milk is similar to 
that of the women’s, but not unctuous. 
Curd from the milk of the goat is abundant, 
of a firmer consistence than that of the 
cow, and retains less whey. Curd from 
ewe’s milk is fat and viscid : that from 
mare’s milk is very similar to what is obtain- 
ed fi’om women’s milk. 
4. The serum, or whey, constitutes a 
great proportion of the milk, and shews the 
following varieties. That from the milk of 
the cow has a greenish cast, a sweet taste, 
contains sugar of milk and neutral salts. 
The whey from women’s milk has little co- 
lour; but contains much saccharine matter. 
The whey of asses’ milk is colourless, and 
contains less salts and more sugar than that 
of the cow. Whey of the goat is yellowish, 
and contains very little sugar and saline 
matter. 'Tlie latter is muriate of lime. The 
whey of ewes’ milk is always colourless, 
and contains the smallest quantity of sugar, 
and but a small portion of muriate and phos- 
phate of lime. That of mare’s milk has lit- 
tle colour, and contains a large proportion 
of saccharine matter, and of saline sub- 
stances, 
MILL, is a machine, which by means 
of any adequate force, as steam, water, 
wind, or animal exertion, acqtiires such an 
additional power as enables the machinery 
to act with increased effect, and with the 
requisite regularity. It may be considered 
an axiom, from which very few, if any, de- 
viations are to be found, that the nearer the 
labouring part is to the power, or origin of 
motion, the greater will be the force em- 
ployed ; but that force will be subject to 
such fluctuations, and to such shocks and 
vibrations, as to render the work inaccurate i 
and unequal. In some operations this is of 
less importance than in such as are con- 
nected with minute and delicate manufac- 
tures. Thus in brass, copper, and fulling- 
mills, the large hammers which perform the 
heavy work derive their motion immediately 
from the great wheel which is turned by 
the stream ; ' they being lifted by cogs, 
or teeth, set on its axis, and working 
without any intermediate machinery. In 
saw-mills, the blades which cut the timbers 
into planks, <kc. are more removed from the 
great wheel by the intervention of other 
wheels, which not only give increased velo- 
city, but relieve the saws from those jerks 
and strains to which they would be subject 
if deprived of those movements which ren- 
der their own operations equable and firm. 
In corn mills the velocity is again increased 
by another course added to the system, 
while the action of the grinding parts is 
thus effectually discharged from all inequa- 
lities of motion ; and thus flour, &c. may be 
ground with certainty to any desired de- 
gree of fineness, according as the distances 
between the stones may be regulated. With 
regard to the more complex movements re- 
quired in the manufacture of silk, cotton, 
&c. many of them are so remotely connect- 
ed with the moving power, that they may 
be made to revolve with the most wonder- 
ful exactness. It is, however, necessary, 
that the frame- work of a mill should be very 
firm and substantial ; that the pinions, 
spindles, and axles, all move freely in their 
sockets, which should be exactly at right 
angles with them; and that no greater 
pressure should take place on any part than 
the duty it is to perform may render neces- 
sary. These great principles are insepar- 
able from the proper construction of mills. 
We consider a knowledge of the powers of 
mechanism to be absolutely indispensable 
towards a due understanding of this subject; 
and recommend the student to refer to 
the head of Mechanics for such informa- 
tion as may enable him to form a more cor- 
rect judgment of the particulars relating to 
mill-work in general. 
With respect to machinery moved by 
steam we need say little in this place ; since 
the movements dependant on that kind of 
power may be found under that article, 
while the more remote or subordinate parts 
will, be seen in the construction of such 
mills as derive their action from wind or 
water. The selection of the power is not 
always within our choice; but must depend 
on the abundance of fuel, the supply of wa- 
ter, and the due elevation of the spot where 
the mill is to be erected. Where coals 
are cheap, the steam engine being so im- 
mensely forcible, and capable of any de- 
sirable bulk, is in most instances preferred. 
Where fuel is dear, and that a stream of 
